Calcitonin Receptor Neurons in the Mouse Nucleus Tractus Solitarius Control Energy Balance via the Non-aversive Suppression of Feeding

To understand hindbrain pathways involved in the control of food intake, we examined roles for calcitonin receptor (CALCR)-containing neurons in the NTS. Ablation of NTS Calcr abrogated the long-term suppression of food intake, but not aversive responses, by CALCR agonists. Similarly, activating CalcrNTS neurons decreased food intake and body weight but (unlike neighboring CckNTS cells) failed to promote aversion, revealing that CalcrNTS neurons mediate a non-aversive suppression of food intake. While both CalcrNTS and CckNTS neurons decreased feeding via projections to the PBN, CckNTS cells activated aversive CGRPPBN cells while CalcrNTS cells activated distinct non-CGRP PBN cells. Hence, CalcrNTS cells suppress feeding via non-aversive, non-CGRP PBN targets. Additionally, silencing CalcrNTS cells blunted food intake suppression by gut peptides and nutrients, increasing food intake and promoting obesity. Hence, CalcrNTS neurons define a hindbrain system that participates in physiological energy balance and suppresses food intake without activating aversive systems. [Display omitted] •NTS Calcr mediates food intake suppression but not aversive responses to sCT•Activating NTS Calcr neurons non-aversively suppresses feeding•These neurons act via non-CGRP PBN neurons•These neurons control long-term energy balance, not just short-term feeding While the hindbrain is often postulated to control only short-term parameters of feeding via circuits that mediate aversive responses when activated strongly, Cheng et al. have identified a hindbrain system that participates in the physiological control of energy balance and suppresses food intake without activating aversive systems or symptoms.